Bcl-۲ May Contribute to Evolution of Endometrial Hyperplasia, but It Isn’t a Factor in Subsequent Carcinogenesis

ABSTRACTEndometrial carcinoma is common in the western world and is increasing in frequency in developing countries as well. Endometrial hyperplasia is considered to be a precancerous lesion. Apoptosis plays an important role in the neoplastic transformation of cells, with Bcl-۲ being an anti-apoptotic cellular marker. Bcl-۲ may have an important contribution to the development of endometrial carcinoma. The aim was to evaluate and compare the expression of markers Bcl-۲ through the spectrum of normal endometrium, endometrial hyperplasias and endometrial adenocarcinomas. ۵۰ cases were included in this study, comprising of ۱۰ cases of normal endometrium, ۱۰ cases of endometrial hyperplasia without atypia, ۱۰ cases of atypical endometrial hyperplasia and ۲۰ cases of endometrial adenocarcinomas from January ۲۰۱۷ to June ۲۰۱۸. Immunohistochemical staining with Bcl-۲ was performed and the results were analyzed.Bcl-۲ staining showed an increase in cases with strong intensity of staining from normal endometrium (۲۰% cases) to cases of endometrial hyperplasia (۷۵% cases). There was, however a decrease in the number of cases with strong intensity Bcl-۲ staining as the lesions progressed from endometrial hyperplasia to endometrial carcinoma (۳۰% cases). The results were statistically significant (P =۰.۰۰۳۰۹). However, there was no significant association of staining between atypical hyperplasia and endometrial carcinomas (p=۰.۴۲۹), as well as the degree of carcinoma (p=۰.۶۹۰۳).Bcl-۲ expression showed an increase from cases of normal endometrium to endometrial hyperplasia supporting the process of increased anti- apoptotic activity in endometrial hyperplastic lesions. Its decreased expression in endometrioid adenocarcinoma when compared to endometrial hyperplasias could point towards other mechanisms of carcinogenesis other than failure of apoptosis.

Keywords:

Bcl-۲ , Endometrium , Endometrial hyperplasia , Endometrial hyperplasia with atypia , Endometrial carcinoma